JPH0259306B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an oscillating compressor that can change compression capacity.

[Prior art]

2. Description of the Related Art A swing type compressor is conventionally known in which a swing plate is driven by a rotating swash plate, and a piston connected to the swing plate is reciprocated to compress fluid (refrigerant). Furthermore, the inclination angle of the rocking plate is substantially changed according to the swash plate, thereby changing the stroke amount of the piston attached to the rocking plate, thereby increasing the compression capacity (compression ratio). ) There are also compressors that change the

The above-mentioned variable capacity compressor generally has a variable angle swash plate attached to the rotor of the main shaft, which oscillates to follow this swash plate, and whose inclination angle changes as the angle of the swash plate changes. The piston has a variable oscillating plate, and the piston connected to the oscillating plate changes the stroke amount as the inclination angle of the oscillating plate changes, thereby changing the compression capacity.

However, in conventional compressors, not only is the structure for changing the inclination angle of the swash plate very complicated, but also the oscillation center of the swash plate is determined within a certain range. The main shaft was passed through the center of the plate, but in order to change the angle of inclination of the swash plate and swing plate, the through hole was made larger than the diameter of the main shaft, making it unnecessary for the swing plate. There was a problem that vibration occurred.

[Purpose of the invention]

An object of the present invention is to provide a variable capacity rocking type that has a very simple mechanism for changing the inclination angle of the swash plate and that does not cause unnecessary rocking of the rocking plate. The purpose is to provide a compressor.

[Structure of the invention]

According to the present invention, a rotor is disposed in a crank chamber formed in a compressor housing and attached to the inner end of a main shaft, and a swash plate is supported by the rotor via a hinge mechanism and whose inclination angle with respect to the main shaft changes. a rocking plate disposed on the inclined surface of the swash plate; and a slider member attached to one end of the rocking plate and disposed to be slidable in a slider groove formed in the compressor housing. The slider member slides within the slider groove in accordance with the rotation of the swash plate, thereby swinging the oscillating plate to reciprocate the plurality of pistons, adjusting the crank chamber pressure, and using the hinge mechanism. In a variable capacity oscillating compressor, which changes the inclination angle of the oscillating plate within a specified range to change the stroke amount of the piston, the oscillating plate has a ball joint at its center that allows the oscillating plate to move along the spherical axis by a ball joint at its center. a first biasing means that is slidably supported and biases the rocking plate in the direction of the main axis via a ball joint; the second biased to
a biasing means, and the inclination angle of the rocking plate is changed based on the biasing forces of the first and second biasing means and the pressure in the crank chamber. A variable oscillating compressor is obtained.

〔Example〕

Hereinafter, the present invention will be explained with reference to embodiments shown in the drawings.

First, the structure of a compressor according to the present invention will be explained with reference to the drawings.

A cylinder block 2 in which a cylinder bore 2a is formed is formed at one end of a cylindrical cylinder casing 1, and a through hole 3a for inserting a main shaft 4 into the center is bored in the opening at the other end.
A front housing 3 in which a radial bearing 5 for rotatably supporting the main shaft 4 is press-fitted is arranged and fixed in the through hole 3a.

A main shaft lead-out cylinder 3b is provided at the outer end of the through-hole 3a of the front housing 3 and protrudes to enclose the main shaft 4. The space formed by the main shaft 4 and the inner wall of the main shaft lead-out cylinder 3b is used as a seal chamber. A mechanical seal 7 is arranged as 6. A crank chamber 1a is formed between the inner wall of the front housing 3 and one end surface of the cylinder block 2, and a disc-shaped cam rotor 8 is fitted to the end of the main shaft 4 within the crank chamber 1a. One end of the cam rotor 8 is bent so as to be substantially parallel to the main shaft 4, and has an ear portion 8a formed in an ear shape. A long hole 8a is provided in this ear portion 8a.

Next, a ball bearing 1 is attached to the inner periphery of the ring-shaped member 9, which is provided with a protrusion 9a at one end of the outer periphery.
0 is press-fitted into the protrusion 9a, and a through hole is provided in the protrusion 9a, into which a pin-like member 9a is inserted and fixed, and this pin-like member 9b
is also inserted into the elongated hole 8b of the ear portion 8a, and the cam rotor 8 supports the ring-shaped member 9 via this pin-shaped member 9b. Note that the pin-shaped member 9b can slide within the elongated hole 8a. In this way, a so-called hinge mechanism is constructed, and the cam rotor 8 and the ring-shaped member 9 are connected by the hinge mechanism, so that the ring-shaped member 9 substantially forms a swash plate.

The rocking plate 11 is shaped like a partition plate and has a hollow cylindrical protrusion 11C in the center thereof, and the protrusion 11C is press-fitted into the inside of the ball bearing 10. At this time, there is a slight gap between the ring-shaped member 9 and the rocking plate 11.
A thrust race 12 is arranged on the ring-shaped member 9 and the rocking plate 11, and a thrust needle bearing 13 is sandwiched between the thrust races.

A spring 14 is disposed between the end of the main shaft 4 and the swing plate 11 through a hollow portion of the cylindrical protrusion 11C. A ball socket 15 having a ball 15a at the tip is attached to the center of the swing plate 11, and the swing plate 11 is supported so as to be swingable by sliding on the ball 15a. This ball socket 15 is fitted into a central hole provided in the center of the cylinder block 2, and is movable in the axial direction, but is prevented from rotating.A coil spring 15a is disposed inside to move the ball 15a in the axial direction. is energized. Note that the biasing force of the coil spring 15b is due to the biasing force of the screw 15 screwed into the center hole.
It can be adjusted by turning c.

Furthermore, an ear shaft 11a protruding toward the cylinder casing 1 is provided at the end of the rocking plate 11.
A slider groove 1b is provided correspondingly, and the ear shaft 11a is slidably disposed in the slider groove 1b via a cylindrical slider 11b.

Further, one end of a piston rod 16 is rotatably supported on the rocking plate 11.
is connected at its other end to a piston 17 located within the cylinder bore 2a. Note that a plurality of pistons having the above-described structure are provided on the swing plate 11.

A suction hole 18 for sucking in fluid and a discharge hole 19 for discharging fluid are bored in one end surface of the cylinder bore 2a. A valve plate 20 to which a valve and a discharge valve are connected is connected to the cylinder block 2 via a gasket (not shown), and a suction chamber 22 and a discharge chamber 23 are formed by a cylinder head 21 having a partition wall 21a. like,
Gasket the cylinder head 21 (not shown).
is disposed at one end of the valve plate 20 via the valve plate 20.
Then, the cylinder head 21 is fixed on the cylinder block 2, and the cylinder casing 1 is closed.

Further, the suction chamber 22 and the crank chamber 1a are communicated through a communication pipe 24, and a solenoid valve 25 is attached to the communication pipe 24 to control opening and closing of the communication pipe 24.

Next, the operation of the above-mentioned oscillating compressor will be explained with reference to the drawings.

When rotational motion is applied to the main shaft 4 by an engine or the like, the rotational motion is transmitted to the cam rotor 8 fitted to the main shaft 4, and this rotational motion is further transmitted to the rocking plate 11 attached to the ring-shaped member 9. is transmitted to. However, since the ear shaft 11a attached to the swing plate 11 slides within the slider groove 1b, the movement of the swing plate 11 in the rotational direction of the cam rotor 8 is prevented. Therefore, the rotational motion transmitted to the rocking plate 11 by the cam rotor 8 is converted into a rocking motion by the rotation of the ring-shaped member 9.

When the rocking plate 11 swings, the piston 1 is moved through the piston rod 16 connected to the rocking plate 11.
7 performs reciprocating motion. Here, when the solenoid valve 25 is opened, the cylinder bore 2 is opened by the operation of the compressor.
Since the blow-by gas leaking from a into the crank chamber 1a escapes to the suction chamber 22, the pressure inside the crank chamber 1a decreases and becomes equal to the pressure in the suction chamber 22.

On the other hand, the pistons arranged on the rocking plate 11 at equal angular intervals apply a reaction force due to gas compression to the rocking plate 11 during the compression stroke. The resultant force of this reaction is received by the hinge mechanism described above. The moment acting on the hinge mechanism due to the force acting on each piston is the swing plate 11 in the figure.
Since the moment exerted by the piston (not shown) located at the lower end of is larger, the moment (M ₁ ) that rotates the rocking plate 11 to the right in the figure eventually acts on the hinge mechanism.

Here, the spring 14 and the ball socket 1
The moment generated in the hinge mechanism due to the resultant force (difference) with M ₂ and the crank chamber 1a and the suction chamber 2 is
If the moment generated in the hinge mechanism due to the pressure difference between the two is _M3 , then in the above case, since the pressures in the crank chamber 1a and the suction chamber 22 are equal,
The only moment in the opposite direction to M ₁ is M ₂ . Therefore, set the spring 14 in advance so that M ₁ > M ₂ .
If the resultant force (difference) between the oscilloscope and the ball socket 15 is determined, the inclination angle of the rocking plate 11 will increase due to the clockwise moment about the hinge mechanism. Note that the tilt angle of the swing plate 11 is inclined until the pin-like member of the hinge mechanism moves to the upper end of the elongated hole 8b, and the tilt angle of the swing plate 11 becomes maximum with respect to the main shaft 4. (Based on the case where the rocking plate 11 and the main shaft 4 are at right angles.)
As a result, the stroke of the piston 17 becomes larger and the compression capacity becomes larger. (Note that this is the time of normal operation of the compressor.) Next, when the solenoid valve is closed, the pressure inside the crank chamber 1a is increased by the blow-by gas leaked from the cylinder bore 2a to the crank chamber 1a during the compression stroke. will rise. Therefore, the moment M ₃ acts to the left around the hinge mechanism, and at a certain point, M ₁ < M ₂ + M ₃ and the moment acts to the left on the swing plate 11 around the hinge mechanism. However, the inclination angle of the rocking plate 11 gradually becomes smaller.
Then, the inclination angle of the rocking plate 11 becomes smaller until the pin-shaped member 9b of the hinge mechanism moves to the lower end of the elongated hole 8b, and as a result, the stroke inside the piston 17 becomes smaller and the compression capacity decreases. The size of the elongated hole 8b of the hinge mechanism is determined so that the minimum compression capacity is 20 to 30% of the maximum compression capacity so that the piston stroke does not become zero in order to circulate lubricating oil. .

Furthermore, since the rocking plate 11 is supported by the ball socket 15 so that its center coincides with the main axis, vibrations in the vertical and horizontal directions do not occur due to rocking.

〔Effect of the invention〕

As established above, in the variable capacity oscillating compressor according to the present invention, the rotor attached to the inner end of the main shaft and the swash plate are connected by a hinge mechanism, and the swash plate is connected by the hinge mechanism. can change its inclination angle within a predetermined range, and furthermore, a rocking plate disposed on the inclined surface of the swash plate is supported by a ball joint at its center so as to be slidable on the ball joint. ,
Furthermore, the first biasing means biases the rocking plate in the direction of the main axis via the ball joint, and the second biasing means biases the rocking plate due to the first biasing means. Since the force is applied in the opposite direction, not only can the inclination angle of the rocking plate be changed by a simple mechanism, but the center of rocking of the rocking plate remains constant, which eliminates unnecessary vibrations. can be prevented.

[Brief explanation of the drawing]

The drawing is a sectional view showing the variable capacity oscillating compressor according to the present invention in a state where the inclination angle of the oscillating plate is at its minimum. 1... Cylinder casing, 2... Cylinder block, 3... Front housing, 4... Main shaft, 5... Radial bearing, 6... Seal chamber, 7... Mechanical seal, 8... Cam rotor, 9... Ring shaped member, 10... ball bearing, 11... rocking plate, 12... thrust race, 13... thrust needle bearing, 14
... Spring, 15 ... Ball socket, 16
...Piston rod, 17...Piston, 18...
...Suction hole, 19...Discharge hole, 20...Valve plate, 21
...Cylinder head, 22...Suction chamber, 23...
...Discharge chamber, 24...Communication pipe, 25...Solenoid valve.

Claims (1)

[Claims] 1. A rotor disposed in a crank chamber formed in a compressor housing and attached to the inner end of a main shaft, a swash plate supported by the rotor via a hinge mechanism and whose inclination angle with respect to the main shaft changes, and the swash plate. a swinging plate disposed on an inclined surface of the plate; and a slider member attached to one end of the swinging plate and slidably arranged in a slider groove formed in the compressor housing; The slider member slides within the slider groove in accordance with the rotation of the swash plate, thereby swinging the oscillating plate to reciprocate the plurality of pistons, adjusting the pressure in the crank chamber, and adjusting the crank chamber pressure. In the variable capacity oscillating compressor, the inclination angle of the oscillating plate is changed within a range defined by a hinge mechanism to change the stroke amount of the piston, and the oscillating plate has a spherical shape at its center. a first biasing means that is slidably supported on the ball arm by a joint and biases the swing plate in the direction of the main axis via the ball joint; A second biasing device that biases in a direction opposite to the biasing direction of the biasing means.
a biasing means, and the inclination angle of the rocking plate is changed based on the biasing forces of the first and second biasing means and the pressure in the crank chamber. Variable oscillating compressor.